rspec users - Sep 2008 - Conditionally turning some specs on and off depending on runtime platform

Hi folks,

Wondering what the best (that is, neatest and most supported) way to  
conditionally turn off some specs depending on the runtime platform.

Background: some of my specs call out to some third-party tools that  
may or may not be installed on the system. I''d like to check for the  
presence of those tools and gracefully skip those specs rather than  
just bombing out.

The following trick, calling "pending" from inside the before block,  
effectively does what I want. But I''m wondering if I can count on this
behaviour going forward? What do you think?

   describe ''Something'' do
     before do
       if required_tools_not_installed
         pending ''not running on this platform''
       end
     end

     it ''should do something'' do
       1.should == 1
     end
   end

Cheers,
Wincent

On Sep 25, 2008, at 9:50 pm, Wincent Colaiuta wrote:
> The following trick, calling "pending" from inside the before
block,
> effectively does what I want. But I''m wondering if I can count on
> this behaviour going forward? What do you think?
>
>  describe ''Something'' do
>    before do
>      if required_tools_not_installed
>        pending ''not running on this platform''
>      end
>    end
>
>    it ''should do something'' do
>      1.should == 1
>    end
>  end
Hi Wincent

How about wrapping it this way instead...

  describe ''Something'' do
    if required_tools_installed
      it ''should do something'' do
        1.should == 1
      end
    end
  end

That will make them invisible (for better or worse).

How come you need this?  Is what you really need to spec that the tool  
itself degrades gracefully? eg

  describe ''Something'' do
    if required_tools_installed
      it ''should do something'' do
        1.should == 1
      end
    else
      it ''should inform the user the tool is missing''
    end
  end

Ashley

-- 
http://www.patchspace.co.uk/
http://aviewfromafar.net/

El 26/9/2008, a las 13:30, Ashley Moran  
<ashley.moran at patchspace.co.uk> escribi?:
> On Sep 25, 2008, at 9:50 pm, Wincent Colaiuta wrote:
>
>> The following trick, calling "pending" from inside the before
block,
>> effectively does what I want. But I''m wondering if I can count
on
>> this behaviour going forward? What do you think?
>>
>> describe ''Something'' do
>>   before do
>>     if required_tools_not_installed
>>       pending ''not running on this platform''
>>     end
>>   end
>>
>>   it ''should do something'' do
>>     1.should == 1
>>   end
>> end
>
> Hi Wincent
>
> How about wrapping it this way instead...
>
>  describe ''Something'' do
>    if required_tools_installed
>      it ''should do something'' do
>        1.should == 1
>      end
>    end
>  end
>
> That will make them invisible (for better or worse).
Yeah, that''s another way of doing it.
> How come you need this?  Is what you really need to spec that the tool
> itself degrades gracefully? eg
>
>  describe ''Something'' do
>    if required_tools_installed
>      it ''should do something'' do
>        1.should == 1
>      end
>    else
>      it ''should inform the user the tool is missing''
>    end
>  end
No, it''s actually a case of having a bunch of Java junk installed on  
my local system which I can use to do extended testing of things like  
feed validity on this machine, while on the server I don''t have (and  
can''t install) the Java stuff so would like to skip those specs.

Cheers,
Wincent

On Thu, Sep 25, 2008 at 3:50 PM, Wincent Colaiuta <win at wincent.com>
wrote:
> The following trick, calling "pending" from inside the before
block,
> effectively does what I want. But I''m wondering if I can count on
this
> behaviour going forward? What do you think?
Pending is not going anywhere.

Cheers,
David

On Sep 25, 2008, at 4:50 PM, Wincent Colaiuta wrote:
> Hi folks,
>
> Wondering what the best (that is, neatest and most supported) way to  
> conditionally turn off some specs depending on the runtime platform.
>
> Background: some of my specs call out to some third-party tools that  
> may or may not be installed on the system. I''d like to check for
the
> presence of those tools and gracefully skip those specs rather than  
> just bombing out.
>
> The following trick, calling "pending" from inside the before
block,
> effectively does what I want. But I''m wondering if I can count on
> this behaviour going forward? What do you think?
>
>  describe ''Something'' do
>    before do
>      if required_tools_not_installed
>        pending ''not running on this platform''
>      end
>    end
>
>    it ''should do something'' do
>      1.should == 1
>    end
>  end
>
> Cheers,
> Wincent
Just wrap your platform dependent specs in an "if".  I used to have  
specs which would fail on ruby 1.8.5, and so I did something like the  
following:

unless on_ruby_1_8_5?
   it "should..." { }
end

Scott


>
>
>
>
> _______________________________________________
> rspec-users mailing list
> rspec-users at rubyforge.org
> http://rubyforge.org/mailman/listinfo/rspec-users

El 26/9/2008, a las 14:59, "David Chelimsky" <dchelimsky at
gmail.com>
escribi?:
> On Thu, Sep 25, 2008 at 3:50 PM, Wincent Colaiuta <win at
wincent.com>
> wrote:
>> The following trick, calling "pending" from inside the before
block,
>> effectively does what I want. But I''m wondering if I can count
on
>> this
>> behaviour going forward? What do you think?
>
> Pending is not going anywhere.
I didn''t think so... I was mostly concerned about the fact that I am  
(ab)using it by calling it from inside the "before" block...

Cheers,
Wincent

On Fri, Sep 26, 2008 at 8:42 AM, Wincent Colaiuta <win at wincent.com>
wrote:
> El 26/9/2008, a las 14:59, "David Chelimsky" <dchelimsky at
gmail.com>
> escribi?:
>
>> On Thu, Sep 25, 2008 at 3:50 PM, Wincent Colaiuta <win at
wincent.com> wrote:
>>>
>>> The following trick, calling "pending" from inside the
before block,
>>> effectively does what I want. But I''m wondering if I can
count on this
>>> behaviour going forward? What do you think?
>>
>> Pending is not going anywhere.
>
> I didn''t think so... I was mostly concerned about the fact that I
am
> (ab)using it by calling it from inside the "before" block...
That doesn''t strike me as abuse :)

Though - we have talked about adding support for arbitrary tags which
could be exposed to the runner and let you do arbitrary things (like
only running examples with or without certain tags). Maybe, someday
...
>
> Cheers,
> Wincent
>
>
>
> _______________________________________________
> rspec-users mailing list
> rspec-users at rubyforge.org
> http://rubyforge.org/mailman/listinfo/rspec-users
>

On Fri, Sep 26, 2008 at 5:13 AM, Wincent Colaiuta <win at wincent.com>
wrote:
>
> No, it''s actually a case of having a bunch of Java junk installed
on my
> local system which I can use to do extended testing of things like feed
> validity on this machine, while on the server I don''t have (and
can''t
> install) the Java stuff so would like to skip those specs.
>
It seems to me that if the tests are useful to run on your local system,
they would be equally useful to run on the server. Otherwise, why run the
server tests at all? They are obviously not going to catch any errors that
the Java code catches.

///ark
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El 26/9/2008, a las 16:16, "David Chelimsky" <dchelimsky at
gmail.com>
escribi?:
> On Fri, Sep 26, 2008 at 8:42 AM, Wincent Colaiuta <win at
wincent.com>
> wrote:
>> El 26/9/2008, a las 14:59, "David Chelimsky" <dchelimsky
at gmail.com>
>> escribi?:
>>
>>> On Thu, Sep 25, 2008 at 3:50 PM, Wincent Colaiuta  
>>> <win at wincent.com> wrote:
>>>>
>>>> The following trick, calling "pending" from inside
the before
>>>> block,
>>>> effectively does what I want. But I''m wondering if I
can count on
>>>> this
>>>> behaviour going forward? What do you think?
>>>
>>> Pending is not going anywhere.
>>
>> I didn''t think so... I was mostly concerned about the fact
that I am
>> (ab)using it by calling it from inside the "before" block...
>
> That doesn''t strike me as abuse :)
Glad to hear you think so!

The truth is, sticking the check in the "before" block
"feels" right,
at least to me, because asking "can I run this example?" is something
that I (obviously) want to do _before_ running each example. Bonus is  
that the examples in question print out the pending message rather  
than just disappearing into the nether.

In contrast, nesting all the affected examples inside a large "if"  
feels much nastier.

Cheers,
Wincent

On Sep 26, 2008, at 10:31 AM, Wincent Colaiuta wrote:
> El 26/9/2008, a las 16:16, "David Chelimsky" <dchelimsky at
gmail.com>
> escribi?:
>
>> On Fri, Sep 26, 2008 at 8:42 AM, Wincent Colaiuta <win at
wincent.com>
>> wrote:
>>> El 26/9/2008, a las 14:59, "David Chelimsky"
<dchelimsky at gmail.com>
>>> escribi?:
>>>
>>>> On Thu, Sep 25, 2008 at 3:50 PM, Wincent Colaiuta  
>>>> <win at wincent.com> wrote:
>>>>>
>>>>> The following trick, calling "pending" from
inside the before
>>>>> block,
>>>>> effectively does what I want. But I''m wondering if
I can count
>>>>> on this
>>>>> behaviour going forward? What do you think?
>>>>
>>>> Pending is not going anywhere.
>>>
>>> I didn''t think so... I was mostly concerned about the fact
that I am
>>> (ab)using it by calling it from inside the "before"
block...
>>
>> That doesn''t strike me as abuse :)
>
> Glad to hear you think so!
>
> The truth is, sticking the check in the "before" block
"feels"
> right, at least to me, because asking "can I run this example?"
is
> something that I (obviously) want to do _before_ running each  
> example. Bonus is that the examples in question print out the  
> pending message rather than just disappearing into the nether.
>
> In contrast, nesting all the affected examples inside a large
"if"
> feels much nastier.
I don''t think so.  In fact, I''ve seen it in spec''s
codebase itself,
where they skipped some examples for jruby, but not for MRI.

Here is another variation on the technique:

pend_if_on_ruby_1_8_5 do
... your examples here ..
end

def pend_if_on_ruby_1_8_5
   if RUBY_VERSION == "1.8.5"
	xit "Skipping examples because on 1.8.5"
   else
	yield
   end
end

Scott